Fig 2: Myeloid-specific Pkm2-deficient mice showed less PMN infiltration. (A) Degranulation of secondary and tertiary granules represented by the release of lactoferrin and MMP9 in PMN isolated from WT and Pkm2-/-, respectively. (B) ROS production in neutrophils following fMLP and PMA induction. (C) Impaired degranulation of secondary/tertiary granules in PMN isolated from Pkm2-/- mice with PMA induction. Degranulation of secondary/tertiary granules was detected by measuring the surface CD11b level. (D) Impaired fMLP-induced trans-filter migration in PMN isolated from Pkm2-/- mice as measured by the MPO optical density (OD). (E) Impaired zymosan-induced PMN peritoneal infiltration in Pkm2-/- mice. Data are represented as mean ± SEM. NS, No significance. *, p < 0.05. **, p < 0.01. ***, p < 0.001.

Fig 3: Effect of PKM on glucose-associated metabolites. (A) Mass isotopomer analysis of 3-phosphoglycerate/2-phosphoglycerate, phosphoenolpyruvate and pyruvate in 4T1/Cas9, 4T1/PKM-KO, 4T1/KO+hPKM1 and 4T1/KO+hPKM2 cells cultured with 13C6-glucose for 8h. (B) Relative metabolite abundance in 4T1/Cas9, 4T1/PKM-KO, 4T1/KO+hPKM1 and 4T1/KO+hPKM2 cells.

Fig 4: PKM is differentially expressed in tumors.

Fig 5: Extracellular Hsp90α boosts the ePKM2-GRP78-AKT pathway. (A) A549-conditioned media was collected and immunoprecipitated with IgG or anti-GRP78 antibodies. The immunoprecipitated samples were subjected to WB analysis with the indicated antibodies to detect the interaction between PKM2 and GRP78. (B) Pull-down assay showing the interaction between PKM2 and cell surface GRP78. Recombinant PKM2 was coupled to cyanogen bromide-activated Sepharose beads and was incubated with crude fractions of the plasma membrane of A549 cells. (C) Co-localization between rPKM2 labeled with Alexa Fluor 488 (AF-PKM2) and GRP78 in A549 cells treated with or without rHsp90α. Scale bar, 20 μm. (D) rHsp90α enhances the interaction between rPKM2 and cell surface GRP78. Crude fractions of the plasma membrane of A549 cells were extracted and immunoprecipitated with IgG or anti-GRP78 antibodies treated with rPKM2 and rHsp90α. (E) A549-sh Ctrl and A549-sh GRP78 cells were treated with rPKM2 (5 μg/ml), rHsp90α (5 μg/ml), or the combination of Hsp90α and PKM2 for 15 min. Akt phosphorylation levels were detected by western blotting.